5.4.2 Power Management Unit (PMU)

The Power Management Unit interface provides monitoring and management of the robot’s power system, including battery status, voltage and current monitoring, and more.

Core Features

Battery Monitoring

  • Battery Voltage: Real-time monitoring of battery voltage

  • Battery Current: Monitors battery charging/discharging current

  • Battery Health: Tracks overall battery health status

Power Management

  • Multi-channel Power Rails: Monitors 48V, 12V, 5V and other power rails

  • Current Monitoring: Tracks current consumption of each module

  • Voltage Monitoring: Tracks voltage status of each module

System Monitoring

  • Module Power Status: Power status of RK3588, ORIN, etc.

  • Over-current Protection: Detects and protects against over-current conditions

Power Management Topic

Topic Name

Data Type

Description

QoS

Frequency

/aima/hal/pmu/state

PmuState

Power management data

-

0.2Hz

  • PmuState ros2-msg @ hal/msg/PmuState.msg

    # PMU State
string pmu_software_version     # PMU software version
string pmu_hardware_version     # PMU hardware version
string pmu_protocol_version     # PMU protocol version
uint32 pmu_bool_status          # Boolean status bits

# Current info (A)
float64 head_power_current      # Head module current
float64 output_48v_current      # 48V output current
float64 rk3588_current          # RK3588 current
float64 output_12v_current      # 12V output current
float64 bus_48v_current         # 48V bus current
float64 orin_current            # ORIN current

# Voltage info (V)
float64 bus_48v_pmos_voltage    # 48V PMOS voltage
float64 battery_voltage         # Battery voltage
float64 fan_voltage             # Fan voltage
float64 output_12v_voltage      # 12V output voltage
float64 output_48v_voltage      # 48V output voltage
float64 bus_48v_voltage         # 48V bus voltage
float64 head_power_voltage      # Head module voltage
float64 orin_voltage            # ORIN voltage
float64 rk3588_voltage          # RK3588 voltage

# BMS info
string bms_manufacturer         # BMS manufacturer
string bms_serial_number        # BMS serial number
string bms_hardware_version     # Hardware version
string bms_software_version     # Software version

uint32 bms_status_bits                      # Status bits

uint16 battery_balance_line_resistance      # Cell balancing line resistance (mΩ)
float64 battery_pack_voltage                # Pack voltage (V)
float64 battery_current                     # Pack current (A, +charge / –discharge)
float64 battery_output_power                # Pack output power (W)
float64 battery_temperature                 # Pack temperature (°C)
uint32 battery_remaining_capacity           # Remaining capacity (mAh)
uint8 battery_remaining_capacity_percentage # Remaining capacity (%)
uint16 battery_cycle_count                  # Cycle count
uint32 battery_cycle_total_capacity         # Accumulated capacity (Ah)

    pmu_bool_status Boolean Bit Definitions:

    Bit

    Name

    Description

    0

    rk3588PowerGood

    RK3588 power good

    1

    rk3588Monitor1

    RK3588 monitor status 1

    2

    rk3588Monitor2

    RK3588 monitor status 2

    3

    orinPowerGood

    ORIN power good

    4

    orinMonitor1

    ORIN monitor status 1

    5

    orinMonitor2

    ORIN monitor status 2

    6

    bus48vOverCurrent

    48V bus over-current

    7

    bus48vOverTemperature

    48V bus over-temperature

    8

    rk3588PlugDetect

    RK3588 plug detect

    9

    orinNXPlugDetect

    ORIN NX plug detect

    10–31

    reserved

    reserved bits

    bms_status_bits Bit Definitions:

    Bit

    Name

    Description

    0

    chargeFlag

    Charging flag

    1

    chargeOverCurrentFlag

    Charge over-current flag

    2

    dischargeFlag

    Discharging flag

    3

    dischargeOverCurrentFlag

    Discharge over-current flag

    4

    shortCircuitFlag

    Battery short-circuit flag

    5

    cellOverVoltageFlag

    Cell over-voltage flag

    6

    cellUnderVoltageFlag

    Cell under-voltage flag

    7

    batteryOverVoltageFlag

    Pack over-voltage flag

    8

    batteryUnderVoltageFlag

    Pack under-voltage flag

    9

    cellOpenCircuitFlag

    Cell open-circuit detected

    10

    ntcOpenCircuitFlag

    Temperature sensor open-circuit detected

    11

    cellDischargeOverTemperatureFlag

    Cell temperature above discharge upper limit

    12

    cellChargeOverTemperatureFlag

    Cell temperature above charge upper limit

    13

    cellDischargeUnderTemperatureFlag

    Cell temperature below discharge lower limit

    14

    cellChargeUnderTemperatureFlag

    Cell temperature below charge lower limit

    15

    reserved_1

    reserved bits

    16

    cellMaxVoltageDiffOverHighFlag

    Max cell voltage difference above limit

    17

    mosfetChargeDisableFlag

    MOSFET charge disabled

    18

    mosfetDischargeDisableFlag

    MOSFET discharge disabled

    19

    mosfetOverTemperatureFlag

    MOSFET over-temperature flag

    20

    balanceLineResistanceOverHighFlag

    Balancing line resistance over limit

    21–31

    reserved_11

    reserved bits

Safety Notes

Warning

Power Management Limitations

  • Power management affects system safety; operate with caution

  • Do not modify power parameters arbitrarily — may cause system damage

  • Power-related operations should be performed under expert guidance

Note

Best Practices

  • Monitor power status regularly to detect abnormalities early

  • Implement monitoring and alert mechanisms for power status

  • Implement power protection strategies

  • Pay attention to temperature and current limits of power modules